blockControlProcessModel

Identify the parameters of a first-order plus time-delay (FOPTD) model of the control process

Information

This block calculates the model parameters of a FOPTD model. Specifically, it employs Buildings.Controls.OBC.Utilities.PIDWithAutotuning.SystemIdentification.FirstOrderTimeDelay.BaseClasses.Gain and Buildings.Controls.OBC.Utilities.PIDWithAutotuning.SystemIdentification.FirstOrderTimeDelay.BaseClasses.TimeConstantDelay to identify the gain, the time constant, and the time delay, respectively.

The calculations are disabled by default. They will be enabled once the tuning period starts, i.e., triSta becomes true. The calculations complete when the tuning period ends, i.e., triEnd becomes true.

Refer to Buildings.Controls.OBC.Utilities.PIDWithAutotuning.Relay.Controller for detailed explanation of the parameters yHig, yLow, and deaBan.

Parameters

TypeNameDefaultDescription
RealyHigHigher value for the output
RealyLowLower value for the output
RealdeaBanDeadband for holding the output value

Connectors

TypeNameDefaultDescription
Buildings.Controls.OBC.CDL.Interfaces.RealInputtOnLength for the on period
Buildings.Controls.OBC.CDL.Interfaces.RealInputtOffLength for the off period
Buildings.Controls.OBC.CDL.Interfaces.RealInputtauNormalized time delay
Buildings.Controls.OBC.CDL.Interfaces.RealInputuOutput of a relay controller
Buildings.Controls.OBC.CDL.Interfaces.BooleanInputtriStaRelay tuning status, true if the tuning starts
Buildings.Controls.OBC.CDL.Interfaces.BooleanInputtriEndRelay tuning status, true if the tuning ends
Buildings.Controls.OBC.CDL.Interfaces.RealOutputkGain
Buildings.Controls.OBC.CDL.Interfaces.RealOutputTTime constant
Buildings.Controls.OBC.CDL.Interfaces.RealOutputLTime delay
Buildings.Controls.OBC.CDL.Interfaces.BooleanOutputtunStaTrue when the autotuning completes successfully

Revisions

  • March 8, 2024, by Michael Wetter:
    Changed deadband to be consistent within the package.
  • June 1, 2022, by Sen Huang:
    First implementation.